Some people are like homing pigeons: Drop them off anywhere, and they’ll find their way around. Other people, though, can’t tell when they’re holding a map upside down. Are the directionally challenged just bad learners? Or are some of us just lucky to be born with a strong internal compass?

Not all of your navigational skills are learned. There’s evidence that your sense of direction is innate. (Some of it, at least.) Your brain is packaged with special navigational neurons—head-direction cells, place cells, and grid cells—and they help program your internal GPS when you’re just a wee tot.

In 2010, two different studies (here and here) explored whether rats were born with a sense of direction. Scientists implanted electrodes in the brains of baby rodents and tracked their neural activity. Although the rats were newborns, the researchers discovered that their head-direction cells (which help us recognize the direction we’re facing) were fully mature. The rats, it seemed, were born with an intrinsic sense of direction. And they hadn’t even opened their eyes yet!

Humans, of course, are not rats. But the hippocampus—the brain region responsible for navigation and spatial memory—is similar in most mammals. If the rat’s internal compass develops this way, then it’s likely that a human’s compass does, too.

Off the Grid

If we’re born with a sense of direction, then why are some people so good at getting lost? The scientists found that the two other cells—place and grid cells—developed within the first month. Place cells are thought to help us form a mental map, while grid cells help us navigate new and unfamiliar places. The two cells interact—and that’s where the trouble might be.

In a 2013 study from Nature, participants played a video game that required them to shuttle back and forth between virtual locations. Monitoring their brains, the scientists found that grid cells helped the gamers keep track of their whereabouts—even without landmarks. According to researcher Michael Kahana and the Daily Mail, it’s a “reasonable assumption that differences in how grid cells work explain why some people have a better sense of direction than others.”

So rejoice, navigationally challenged people! If you’ve ever gotten lost pulling out of your driveway, your may now blame your grid cells.

Of course, the nature-nurture argument isn’t black and white here. Although this neural network is hardwired from the time you’re born, it matures thanks to your interactions with the world. These connections are like the prefab wiring in your house, while your experiences with the environment are like the solder that makes that wiring stronger. Both help.

Will a GPS mess with this wiring?

A GPS may save your behind now and then, but it may meddle with your navigational skills if you depend on it to get everywhere. We naturally get around by using a process called “dead reckoning.” Basically, you estimate where you are by comparing your location to a reference point. You use a mental map to make these estimates. Problem is, when you rely on a GPS, that mental map can get foggy.

A 2005 study at the University of Nottingham asked people to drive to a specific spot. Some of them were given step-by-step directions, while others were handed an old-fashioned map. At the end of their journey, they were asked to sketch out the route they traveled. The folks who were given instructions drew the most inaccurate maps. People who used a GPS to walk around a city faced the same problem.

Two things are to blame. First, when you depend on a GPS, you’re more likely to ignore your surroundings. You don’t memorize as many landmarks because you don’t need to. As a result, your mental map is less detailed. That’s why people who depend on a GPS sometimes panic during detours. By updating the map on their GPS, they fail to update the map in their brain.

The second reason isn’t as earth shattering. A GPS usually prevents you from huge blunders (disclaimer: OK, sometimes not). People who navigate on their own are more likely to screw up. Thankfully, the experience of committing a gaffe actually improves their mental map. Making mistakes remains one of the best ways to learn.